Flavor Text is the lore given to items in the game. Normally, flavor text does not affect gameplay and is just there to give some more background information. However, after the Catastrophe, flavor text is one of the things that begins changing in Theldesia.
Changes in Flavor TextEdit
Several months into the Catastrophe, people begin noticing that their items and weapons were acting differently, but most wrote it off and ignored it, although The Roderick Firm was requested by Shiroe to look into this. Just as the guild announced its discoveries, two distinct cases in Akihabara proved that flavor text indeed became real.
Takayama Misa's scythe, Calamity Hearts, had ominous flavor text that stated it could create disasters in a single swing. True to form, it suddenly activates at Seven Falls, causing Krusty to take the hit for her, disappearing along with her arm.